To help you put things into perspective, selling new brand name knives on eBay is not profitable. Only rarely will a knife sell above dealer cost. Knowing this should automatically lower your expectations for customer service. The seller really can't and shouldn't provide much service when he's selling at a loss.
I use eBay occasionally for inventory clearance. I don't even answer the jillions of questions and emails I get about the auctions. I just can't give things away below cost and add additional work and cost to the effort. I'm willing to ship the product when I get paid. That's about it. eBay is bottom line. It is the way it is. Know that when you get involved in it.
Nevertheless, the seller is responsible for making good on misrepresented products. Misrepresenting them simply makes the loss greater. That also is the way it is.
People with that attitude should not sell on ebay. Treat each person the way you want to be treated.
Communication is the key to everything. I have sold on ebay and bought on ebay. My integrity is worth more than money. There have been one or two times I paid a bit extra out of my own pocket just so the item arrives a bit faster. (Yeah I don't have great business sense, but I will give the best level of service possible, because it is my reputation at stake) This is one thing which is easy to lose and very hard to gain.
take care
aj